Hot zones formation during soot combustion in diesel engines particulate filters

摘要：作者：Dan Luss研究所：休斯顿大学提案号：0625646题目：柴油机微粒过滤器中煤烟燃烧过程中的热区形成知识优点：法规要求大幅减少柴油机的煤烟排放，这导致了收集煤烟的柴油微粒过滤器（DPF）的发展。经验表明，在再生过程中，催化过滤器上形成局部热点，其中煤烟在催化过滤器上燃烧。这对设备的寿命有不利的影响，应该消除或大大减少。有必要了解和预测这些热点的形成及其特征和动态，并确定它们对操作条件和再生程序、颗粒的性质和负载以及催化DPF的性质的依赖。此外，了解沉积颗粒的剖面和整体通道内轴向速度变化对点火和热点形成及动力学的影响。PI计划进行一组实验和理论/数值研究来产生这种理解。实验将利用红外摄像机跟踪碳颗粒沉积的催化过滤器表面的温度。这些实验将提供一组关于这些热点的定量数据。他计划开发和系统地分析一系列不同复杂程度的数学模型的行为特征，以便了解可能导致热点形成的原因并能够预测它们。在DPF中，气体沿垂直于壁面的方向从一个通道流向另一个通道。这导致了整体通道中轴向速度的变化，这在通常的蜂窝流动中是不会遇到的。PI计划研究轴向速度的变化对DPF点火模式和热点形成的影响。该研究将加深对反应、输运和对流耦合形成的时空格局的复杂特征和动态的认识。更广泛的影响：研究的重点将放在研究生和本科生的教育和培训上。该研究将使学生接触到仔细的实验和数据处理，使用现代分析和催化剂表征方法，建模，分析和对流-扩散-反应系统的数值模拟。它将为研究生提供工业和/或学术职业培训，并激励本科生继续研究生学习。PI的研究小组过去为许多本科生提供了研究机会，包括少数民族学生。计划继续这个教育功能。将作出特别努力，扩大代表性不足群体的参与。该研究小组目前的研究生中有一半是女性。研究结果将发表在专业期刊上，并在技术会议上以及在休斯敦大学提供的两年一次的继续教育课程中进行介绍。

ABSTRACTPI: Dan Luss Institution: University of HoustonProposal Number: 0625646Title: Hot zones formation during soot combustion in diesel engines particulate filtersIntellectual Merit: Regulations requiring a drastic reduction in the soot emission by diesel engines have led to the development of diesel particulate filters (DPF) that collect the soot. Experience suggests that local hot spots form on the catalytic filter during the regeneration, in which the soot is burned on the catalytic filter. This has a detrimental impact on the life of the device and should be either eliminated or largely reduced. There exists a need to gain an understanding and ability to predict the formation of these hot spots and their characteristics and dynamics and determine their dependence on the operating conditions and regeneration procedure, properties and loading of the particulates and properties of the catalytic DPF. Moreover, to understand the impact of the profile of the deposited particulates and the axial velocity variation in the monolith channels on the ignition and hot spot formation and dynamics. The PI plans to conduct a combined set of experimental and theoretical/numerical studies to generate this understanding. The experiments will utilize an IR camera to follow the temperature on the surface of the catalytic filter on which carbon particles will be deposited. These experiments will provide a set of quantitative data about these hot spot. He plans to develop and analyze systematically the behavioral features of a sequence of mathematical models of different degrees of complexity in order to gain an understanding of what may cause hot spot formation and an ability to predict them. In a DPF the gas flows from one channel to the second in a direction perpendicular to the wall. This causes variations in the axial velocity in the monolith channels, which are not encountered in the usual honeycomb flow. The PI plans to investigate the impact of this variation in the axial velocity on the mode of DPF ignition and hot spot formation. The research will enhance the understanding of the complex features and dynamics of spatiotemporal patterns formed by the coupling of reaction, transport and convection.Broader Impacts: A strong emphasis of the research will be the education and training of both graduate and undergraduate students. The research will expose the students to careful experimentation and data processing, use of modern analytical and catalyst characterization methods, modeling, analysis and numerical simulations of convection-diffusion- reaction systems. It will provide the graduate students with training for industrial and/or academic careers and motivate the undergraduate students to pursue graduate studies. The PI's research group provided research opportunities for numerous undergraduate students in the past, including minority students. It is planned to continue this educational feature. Special efforts will be directed to broaden the participation of underrepresented groups. Half of the current graduate students in the research group are females. The results of the research will be published in professional journals and presented in technical meetings and in a bi-annual continuing education course offered at UH.